Decipher my opthalmologist's prescription.

I just got two prescriptions for new glasses – one for reading/computer and one for distance. Each slip has 6 columns:

SPH - CYL - AXIS - PRISM - BASE - VERTEX

The first three are filled out (for both right and for left), and the final three are blank.

What to these terms mean?

Here’s a site that has some descriptions of at least the first 5 (my contacts prescription form has all 5 of those, but not “vertex”).

Wikipedia has a pretty good article on eyeglass prescriptions, too